Medicine for Africa - Medical Information Service
ITAMINS from 
to 
Definition:
Vitamins are organic substances that are required as nutrients in very small amounts, because they cannot be synthesized by the human organism itself, and thus need to be added to the daily diet in sufficient amounts. The word ‘vitamin’ is derived from the words ‘vital’ and ‘amine’, although not all vitamins are amines.
Vitamins are classified according to their biological activity, made up of a set of distinct chemical compounds, and grouped alphabetically as ‘generic vitamin descriptors’.
Overall, vitamins have an inherent large variety of biochemical functions, including functions as regulators of cell and tissue growth and differentiation (vitamin A), as hormones (vitamin D), or as antioxidants (vitamin E). The so-called vitamin B-complex, a large collection of different types of vitamins (see below), consists of eight (8) vitamins that function as co-enzymes, bound to enzymes, and thus support cell metabolism in the form of catalysts or substrates.
Some vitamins are fat-soluble – i.e., they are absorbed within the gastrointestinal tract with the help of lipids (fats), and can be stored and accumulated within fat tissue.
Other vitamins are water-soluble – these vitamins are readily excreted via the urinary tract, if the body’s storage capacities have been reached.
In summary, of a total of 13 vitamins, four (4) are fat-soluble vitamins, consisting of vitamins A, D, E and K which accumulate within the body and can cause ‘hypervitaminosis’ – an excessive rise of vitamin levels within the body – with subsequent side effects (see below). All other, water-soluble vitamins (the 8 vitamins in the B-complex and vitamin C) usually are excreted via the urine, if ingested in amounts that extend the body’s storage capacity, and thus, rarely ever cause negative effects due to hypervitaminosis.
Vitamins are essential (absolutely necessary) for the normal growth and development of human organisms and childhood development. Once the body’s growth and development is complete, vitamins still remain essential nutrients that need to be added to the daily diet in order to assure the healthy maintenance of all human cells, tissues and organs.
Vitamin Alphabet – Function – Nutritional Source
Vitamin A – beta carotin, retinols:
Vitamin A is a fat-soluble vitamin and a powerful antioxidant which helps to protect cells against potentially cancer-causing ‘free radicals’ by neutralizing them. Vitamin A has protective effects against heart disease and stroke, lowers elevated cholesterol levels and is said to slow the aging process. It has a positive effect for one’s eye sight, counteracts night blindness, and slows the progression of cataracts and macular degeneration. Furthermore, it has shown to have a protective effect against the occurrence of colds, the flu and infections of kidneys, bladder, lungs and mucous membranes, and the progression of osteoarthritis, skin wrinkling, age-related spots and acne.
Food products containing vitamin A include:
Cod liver oil; liver (beef and chicken); cheese; carrots, spinach, kale, pumpkin; cantaloupe, papaya, mango, pink grapefruit, apricots, peaches; oily fish such as mackerel; milk; liver; fortified oatmeal, margarine and yoghurts.
Vitamin B – complex:
All vitamins of the B complex are water-soluble and excessive amounts of them are excreted via the urine.
Vitamin B1 – thiamin:
Thiamin expresses positive effects onto the nervous system and mental attitude. It assists in blood formation and enhances blood circulation; it helps in the metabolism and digestion of carbohydrates, and plays a key role in the production of energy. Vitamin B1 promotes a healthy muscle tone, has anti-oxidant effects, optimizes brain function and mental alertness, and has some protective effects against the degenerative process of aging.
Food products containing vitamin B1 include:
Beef kidney and liver; dried kidney, navy and garbanzo beans (chickpeas); oranges and orange juice; brown and raw rice; wheat germ, flour, rye and whole grain products; peanuts, raisins and oysters.
Vitamin B2 – Riboflavin:
Riboflavin is an important factor for red blood cell formation, the production of antibodies, as well as cell growth. It has a preventive influence on the development of cataracts and helps to alleviate eye fatigue. Vitamin B2 aids in the metabolism of all three food substances – carbohydrates, proteins and fats, and aids in the release of energy that is derived from food products. It is also supportive in the production of adrenal hormones.
Food products containing vitamin B2 include:
Bananas; dairy products and eggs; pork, ham and beef (liver); mixed vegetables; enriched breads, fortified cereals and wheat germ; tuna fish.
Vitamin B3 – Niacin, niacinamide:
One of the most important effects of niacin is that it dilates blood vessels and thus reduces high blood pressure and increases blood circulation. It also significantly lowers cholesterol and triglyceride levels in the blood, and regulates blood glucose (sugar) levels. It has an overall positive impact on building resistance to stress, to prevent depression, mental illness and migraine headaches by aiding in the functioning of the nervous system. Niacin also stimulates one’s sex drive.
Food products containing vitamin B3 include:
Pork, ham, beef (liver); chicken (white meat) and turkey; halibut, salmon, swordfish and tuna fish; dried beans and peas, potatoes; peanuts and peanut butter; fortified cereals and Brewer’s yeast.
Vitamin B5 – Pantothenic Acid:
Pantothenic acid is considered an anti-stress vitamin, due to its influence on the physiological functioning of the adrenal glands. It also has an important role in the metabolism of hemoglobin and in the detoxifying process of harmful chemicals from the blood (such as insecticides and herbicides). It has a positive effect on boosting one’s physical performance, and it can reduce many adverse and toxic effects of many antibiotics. Furthermore, it is involved in the promotion of red blood cell production and sex hormones, has a positive impact on the metabolism of carbohydrates, proteins and fats, and helps to slow joint degeneration in association with other compounds, thus also slowing the progression of rheumatoid arthritis, osteoarthritis and even discomforts that are associated with menopause.
Food products containing vitamin B5 include:
Avocados, bananas and oranges; broccoli, collard greens, lentils, beans and soy beans; chicken and all kinds of meat, liver; lobster; eggs and blue cheese; peanuts, peanut butter and sunflower seeds; whole grain products including wheat germ.
Vitamin B6 – Pyridoxine:
Pyridoxine has a significant positive impact on reducing the potential of developing heart disease by inhibiting the formation of homocysteine, a chemical compound that exhibits toxic effects on the heart muscle by allowing the deposition of cholesterol within the cardiac muscle. In addition, it helps maintaining the physiological functions of the central nervous system (CNS) and normal brain functions; it reduces the occurrence of muscle spasms, leg cramps and stiffness of joint and promotes red blood cell formation and the production of antibodies.
Food products containing vitamin B6 include:
Avocados and bananas; ground beef, beef liver and ham; chicken; salmon, shrimp and tuna fish; hazelnuts and sunflower seeds; lentils, potatoes and soybeans, wheat germ and fortified cereal.
Vitamin B7 – Biotin:
Biotin is an important co-factor in the utilization of proteins and other nutrients, supports cell growth and plays an important role in the fatty acid production. It may also have a positive impact on lowering the blood glucose levels in patients with both diabetes type 1 and type 2.
Food products containing vitamin B7 include:
Bananas; almonds, cashew nuts, peanuts and peanut butter, and walnuts; meats and (calf) liver; cooked eggs and milk; chicken; clams, mackerels, salmon and tuna fish; oatmeal, oat bran, soybeans, split beans, green peas, brown rice and bulgur wheat.
Vitamin B9 – Folic Acid:
Folic acid has the potential to reduce homocysteine levels in blood, and thus has a somewhat positive impact towards the development of heart attacks. It protects against a number of birth defects by supporting the development of embryonic and fetal nerve cell formation. It has a protective effect against intestinal parasites and food poisoning; it supports the formation of red blood cells and helps strengthening the immune system by supporting the formation of white blood cells (leukocytes).
Food products containing vitamin B9 include:
Avocados, bananas, cantaloupe and citrus fruits and juices; asparagus, Brussels sprouts, cabbage, beans, endive, beets, sprouts, green, leafy vegetables, chickpeas (Garbanzo beans), and lentils; calf liver; Brewer’s yeast, fortified grain products and wheat germ.
Vitamin B12 – Cyanocobalamine:
It is an important adjunct in the formation of red blood cells, proper nerve functions and a healthy immune system. It is required for the proper digestion of food products, the synthesis of protein and the metabolism of carbohydrates and fats. Has a supportive function in the formation of cells and their longevity, prevents nerve damage and improves concentration, memory and general mental abilities.
Food products containing vitamin B12 include:
Beef and beef liver, and liverwurst; clams, flounder, herring, mackerel, oysters, sardines and snapper, dairy products, milk, eggs and Swiss cheese.
Vitamin C – Ascorbic Acid:
Vitamin C is a very potent and important anti-oxidant – its primary role is in the formation of collagen for the growth and repair of body tissue cells, blood vessels, bones, teeth and gums. It protects against the harmful effects of pollution and against the development of infections by enhancing the immune system. Furthermore, it protects against abnormal blood clotting and bruising, and is said to possess protective effects against many kinds of cancer by opposing the formation of nitrosamines (cancer-causing substances). It has a known effect in the treatment of the common cold, prevents scurvy (!) and is vital for wound healing, strengthening blood vessels and reducing the blood cholesterol level.
Food products containing vitamin C include:
Fruits – grapefruit, lemons, guava, mangos, oranges and orange juice, strawberries, papayas, tangerines and tomatoes; vegetables – black currants, Brussels sprouts, cabbage peppers (sweet and hot), kale, spinach, watercress; collards, potatoes.
Vitamin D – Calciferol, cholecalciferol:
Vitamin D is a fat-soluble vitamin that improves the absorption of calcium from the gut and the utilization of both calcium and phosphorus, and thus supports the hardening and repair of bones and the synthesis of collagen. It is an important vitamin in order to prevent rickets and to promote normal growth in children. It supports the immune system, and in connection with calcium, it has proven to reduce osteoporosis and hip fractures. In addition, it is an important co-factor for the islet cells in the pancreas to produce insulin, the hormone that regulates blood glucose levels. Thus, it is also an important factor in the prevention of diabetes type 1, the juvenile type of diabetes. It supports the function of the thyroid gland, and is said to have some preventive effect against the development of colon cancer.
Food products containing vitamin D include:
Cod liver oil, halibut liver oil, herring, mackerel, salmon, sardines, and tuna fish; sunlight; vitamin D-fortified milk and egg substitutes.
Vitamin E – alpha-tocopherol:
Vitamin E is a fat-soluble vitamin that is considered a ‘super anti-oxidant’ due to its protective function on cells against damage caused by ‘free radicals’. Although its exact functions and actions are not yet totally understood, it is considered an important vitamin in preventing several types of cancer (gastrointestinal tract, colon, breast, lung and prostate) and cardiovascular disease (lowers high blood pressure, prevents and dissolves blood clots, improves oxygenation of the blood, lowers the rate of heart attacks), and it has been used in the treatment of premenstrual syndrome and fibrocystic disease of the breast.
When applied topically, vitamin E hastens scar healing and can prevent/alleviate thick scar formation; it aids in preventing cataract of the eye, promotes healthy skin and hair and retards ‘cellular aging’ due to its oxidative effect. It can slow Alzheimer’s disease and strengthens the body’s immune system; it improves muscle strength and stamina and thus relieves leg cramps. And finally, it can also enhance sexual performance.
Food products containing vitamin E include:
Wheat germ and wheat germ oil; asparagus, avocados, broccoli, corn and corn oil and margarine; canola oil, cottonseed oil, soybean oil, safflower oil and nuts; almonds, Brazil nuts, hazel nuts, peanuts and peanut oil, sunflower seeds and walnuts.
Vitamin K – phyllochinone, phylloquinone, phytonadione:
Vitamin K is a fat-soluble vitamin that is essential for the proper functioning in coagulation (blood clotting). It is an important co-factor in the coagulation cascade that prevents uncontrolled bleeding by producing blood clots upon a tissue injury. The body stores very little vitamin K, and stores are rapidly depleted unless the vitamin is regularly provided through dietary intake.
Vitamin K is also an important co-factor in combination with vitamin D for the mineralization (development) of bone. Furthermore, it is important for some proteins that are required for normal cell growth of the nervous system, as well as in the heart, lungs, kidneys, cartilage and stomach.
Food products containing vitamin K include:
Alfalfa, asparagus, broccoli, Brussels sprout, cabbage, green, leafy lettuce, seaweed, spinach and turnip greens; cheddar cheese, and liver.
Symptoms:
Symptoms depend on whether a person suffers of hypovitaminosis – insufficient supply of vitamins to the body, usually due to insufficient dietary intake – primary insufficiency, or whether hypovitaminosis is caused by diseases, syndromes or physiological abnormalities that can interfere with the normal uptake of dietary vitamins from the food that has been consumed – secondary deficiency. Excessive smoking or alcohol consumption as well as drug addicts or the excessive intake of medications can all be the cause of a secondary deficiency of various vitamins.
Hypovitaminosis: [Vitamin – subsequent disease and cause --> symptoms]
Vitamin A (retinol) – xerophthalmia, caused by a dietary lack of animal sources --> night blindness, can lead to blindness in children; increased susceptibility to infection, frequent fatigues, loss of smell and appetite. During pregnancy, increased occurrence of deficiency in the third trimester (because of increased demand from the child) can cause increased night blindness in the mother, and is also associated with an increased mother-to-child HIV transmission.
Vitamin B1 (thiamin) – beriberi, a ‘nutritional disorder’, often present in alcoholics --> nervous system ailment, impaired sensory perception, weakness and pain in the limbs, weight loss, mental depression and constipation.
Vitamin B2 (riboflavin) – deficiency or ‘ariboflavinosis’ in its extreme, caused by insufficient dietary intake, often associated with other vitamin deficiencies --> negative impact on the metabolism of carbohydrates, proteins and fats, leading to cracked lips, inflammation of oral mucosa and tongue epithelium, mouth ulcers, cracks at the corners of the mouth and a sore throat, bloodshot eyes, dermatitis, retarded growth in children.
Vitamin B3 (niacin) – pellagra, caused by alcoholism, chronic diarrhea, gastrointestinal diseases (e.g. ulcerative colitis), liver cirrhosis, carcinoid syndrome, etc. --> headaches, fatigue, muscular weakness, diarrhea, dermatitis and dementia; can ultimately end fatal.
Vitamin B5 (pantothenic acid) – rare by itself, usually occurs in association with other vitamin B deficiencies --> acne, paresthesia, overall weakness, muscle cramping, dizzy spells, restlessness, insomnia and fatigue, water retention, nausea, vomiting or diarrhea.
Vitamin B6 (pyridoxine) – rare by itself, usually occurs in association with other vitamin B deficiencies --> anemia, depression, dermatitis, hypertension (increased blood pressure), water retention, and elevated levels of homocysteine, conjunctivitis, neurologic symptoms of somnolence, confusion and neuropathy.
Vitamin B7 (biotin) – not due to inadequate biotin intake, but rather to the inefficiency to adequately process it (enzyme deficiency) --> decreased appetite and growth development, dermatitis, alopecia (loss of hair) and perosis (shortening and thickening of bones).
Vitamin B9 (folic acid) – a deficiency limits normal cell function (cell division and protein synthesis) and affects normal growth and repair of cells and tissues --> macrocystic anemia, may lead to vitamin B12 deficiency, anemia, premature gray hair, elevated levels of homocysteine, deficiency in pregnant women can lead to birth defects.
Vitamin B12 (cobalamine) – pernicious anemia, caused by the absence or inefficiency of intrinsic factor within the lining of the stomach --> megaloblastic anemia, chronic fatigue, depression and loss of memory, can also cause irreversible damage to brain and nervous system, eye disorders, hallucinations, enlargement of the liver (hepatomegaly), labored breathing, spinal cord degeneration.
Vitamin C (ascorbic acid) – scurvy, also called Barlow’s disease --> spongy gums leading to tooth loss and bleeding gums, dark purplish skin spots (especially on legs), bleeding from mucous membranes, pallor, sunken eyes, nosebleeds, swollen or painful joints, slow-healing wounds and fractures, skin hemorrhage, anemia, impaired digestion.
Vitamin D (cholecalciferol) – rickets, caused by insufficient dietary intake or interference with its uptake, latest research suggests that low levels may be the result of a disease process --> thin, brittle (improperly calcified) bones in children, osteomalacia (bone softening due to defective bone mineralization) in adults, lack of vigor, muscular weakness, retention of phosphorus in the kidneys, inadequate calcium absorption, can severely impede general health status.
Vitamin E (alpha-tocopherol) – rare, due to insufficient uptake or inability to absorb this fat-soluble vitamin --> ataxia (poor muscle coordination), lack of reflexes, paralysis of eye muscles, dry skin, inability to walk, loss of reproductive powers, lack of sexual vitality, abnormal fat deposits in muscles, degenerative changes in the heart.
Vitamin K (phytonadione) – caused by various liver diseases and in liver cirrhosis, due to malabsorption of vitamin K from the intestinal tract, malnutrition and alcoholism --> impaired blood clotting leads to increased bleeding as the major symptom, especially following minor injuries or trivial trauma. Nosebleeds, gastrointestinal bleeding, hematuria (blood in urine) and melena (black colored stool due to bleeding within the intestinal tract), heavy menstrual bleeding, bleeding from gums and easy bruising are all characteristic symptoms. In infants, vitamin K deficiency can result in life-threatening intracranial hemorrhage (bleeding episodes within the skull).
Hypervitaminosis of vitamins is usually a rather rare occurrence since it requires an excessive multifold intake of the needed, recommended or even normally available amount of vitamins, often over a longer period of time, in order to cause any significant symptoms or reactions. The cause is most often the excessive intake or inappropriate metabolism of usually fat-soluble vitamins, such as vitamins A, D, E and K (via intake of excessive vitamin supplements, drugs) that exceed the physiological storage capacity and cannot be excreted by the body. The excess vitamins will be stored in fat tissues and can reach the blood stream in an uncontrollable manner, thus resulting in toxicity symptoms (see below).
Hypervitaminosis of water soluble vitamins is even less likely, because any excess beyond the body’s storage capacity will normally be excreted in the urine via the kidneys (provided the person does not have a kidney disease that may limit normal renal function).
All vitamins are stored in only small amounts by the body – mostly the liver, and thus need to be supplemented regularly through appropriate food intake.
Since every person’s metabolism, vitamin requirements and vitamin storage abilities vary, the concentration of vitamins any one person can tolerate varies greatly – which may explain the fact that most cases of hypervitaminosis occur in children.
Hypervitaminosis: [Vitamin – subsequent disease and cause --> symptoms]
Vitamin A (retinol) – caused by excess intake of retinoids, NOT betacarotene, a pro-vitamin to vitamin A --> systemic toxicity includes nausea and vomiting, headaches and dizziness, blurred vision, and loss of muscular coordination.
Vitamin B3 (niacin) – intake in excess of 2 grams per day can block the breakdown of fats in adipose tissues and thus alter blood lipid levels --> symptoms include liver damage potentially leading to liver failure, hyperglycemia (increased glucose levels in the blood), cardiac arrhythmias (heart beat irregularities), gastrointestinal complaints such as indigestion, as well as skin rash, dry skin, facial flushing and itching.
Vitamin B6 (pyridoxine) – if daily intake exceeds 100 mg --> sensory neuropathic symptoms such as unstable gait, numb feet, paresthesia, and decreased touch sensation can occur; in excessive hypervitaminosis, the severe expression of the above symptoms and developing ataxia (gross incoordination of muscle movements) may take up to six months to resolve.
Vitamin C (ascorbic acid) - symptoms consist of a brief, pronounced laxative effect, i.e diarrhea, and possibly nausea.
Vitamin D ([chole-] calciferol) – probably the most common overdose poisoning with vitamins due to the intake of ‘multivitamin pills’, although a more than 100 times the daily recommended dosage is required for a toxic overdose --> early symptoms are dehydration, vomiting, anorexia (decreased appetite), constipation, fatigue and irritability. Excess vitamin D can cause abnormally high blood levels of calcium (hypercalcemia) with subsequent over-calcification of bones, soft tissues, and kidneys with the development of kidney stones. The symptoms of hypervitaminosis D normally occur several months after exposure of excessive vitamin D intake.
Vitamin E (tocopherol) – hypervitaminosis causes a state of vitamin E toxicity --> since vitamin E also acts as an anticoagulant, it may increase the risk of bleeding problems, as well as subsequent heart problems.
Vitamin K (phyllochinone) --> symptoms include flushing sensations, taste changes, dizziness, sweating, and a rapid and weak pulse; the most important and adverse side effect/contraindication occurs in association with the concomitant intake of coumarin class (warfarin) anticoagulation therapy, which can lead to uncontrollable bleeding episodes and end lethal. Vitamin K is also excreted into breast milk when it can lead to hyperbilirubinemia upon excessive intake by the newborn.
Diagnosis:
Both hypovitaminosis and hypervitaminosis can easily be diagnosed by simple blood tests, once the physical examination (some characteristic symptoms) and patient history point the examining physician into the right direction.
However, it is important to exclude any potential other diseases or disease processes/syndromes (malabsorption, various cancers, liver or kidney failure, certain auto-immune diseases, etc.) that could be the primary cause of the secondarily occurring hypo- or hypervitaminosis.
Treatment:
Hypovitaminosis: secure sufficient intake of the deficient vitamin.
Hypervitaminosis: stop the intake of the excess vitamin, and associated symptoms usually abate after days to weeks to months (depending on the type of hypervitaminosis (see above).
As mentioned above, if the hypo- or hypervitaminosis is secondary to another disease process, obviously, the underlying illness needs to be treated in addition to adjunct vitamin intake (in hypovitaminosis), while hypervitaminosis will usually slowly receed during the treatment of the primary disease process.
Prevention:
Prevention of hypovitaminosis can normally be achieved by maintaining a somewhat balanced diet which includes, at least from time to time, the individual food sources that are rich of one or more vitamins (see above). Most cases of hypovitaminosis occur only after many months, and sometimes years, without even minimal amounts of intake of any specific vitamin. Another cause of hypovitaminosis is the inability of the body to absorb, metabolize or store the vitamin, usually a result of chronic disease processes or some autoimmune diseases.
Hypervitaminosis is not a syndrome that occurs ‘easily’ – it is usually the result of excessive vitamin intake over a long period of time, or the accidental intake of an excessive large amount of one specific vitamin via drugs, or, may be the result of an ineffective way of processing, storing and/or metabolizing the vitamin, usually due to chronic disease processes or autoimmune diseases.
A balanced and prudent diet that consists of meat, poultry and fish, a variety of vegetables, as well as different fruits, can easily protect you from any diseases or syndromes due to insufficient or excessive vitamin intake.
Variety is the major ingredient of any nutritionally valuable meal!
_________________________________________________________________________________
DISCLAIMER: The above article is only intended to provide general information regarding this topic. It is not intended and does NOT replace the need to consult a medical or other professional person, if you have or believe to have this disease/disorder. While the article was researched, written and reviewed by medical professionals, and Medicine for Africa, its staff and publisher made every effort to assure accuracy and correctness, it does not claim to be complete, correct or to reflect the very latest stand of medical/scientific knowledge in the disease’s/syndrome’s pathology, diagnostic and/or therapeutic development. Medicine for Africa, its founder, management, staff, writers, reviewers or publishers may NOT be made responsible or legally bound to any information provided above, and cannot be held liable to any conclusions or decisions the reader may draw after reading this article. The reader is explicitly advised to consult a licensed physician and to present his/her specific situation before making any health related decisions.